Properties of self-reported measures assessing social inclusion in adults diagnosed with mental illness: a systematic review protocol

Abstract Background Social inclusion is widely recognized as a key factor in mental health recovery and overall well-being. However, its conceptualization and measurement remain inconsistent in both research and practice. Few self-reported measures have been developed to assess specifically social inclusion among people diagnosed with mental illness, but many have been developed to measure similar constructs, such as community integration, social/community participation, social/community engagement, social/community involvement, (psycho)social functioning, social well-being, and recovery. The aim of this study is to identify, compare, and synthesize all available self-reported measures for assessing social inclusion and similar constructs among adults diagnosed with mental illness; evaluate their measurement properties; identify potential gaps; and provide recommendations for future research. Methods This systematic review protocol follows the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN). A comprehensive literature search was conducted using four electronic databases: PubMed, PsycInfo, Scopus, and Web of Science. Other studies were identified by checking the references or contacting the authors. A detailed protocol was designed for a systematic literature review of social inclusion measures (and similar concepts) developed, validated, and/or adapted for adults diagnosed with mental illness, including research questions, eligibility criteria, search strategies, data selection and collection processes, assessments of the methodological quality of individual studies and patient-reported outcome measures (PROMs), assessments of the quality of the evidence, and strategies for data syntheses. Discussion Given the complexity of and the lack of consensus around the social inclusion of people with mental illness as well as the increasing number of measures, a systematic review is both timely and necessary. A multidimensional approach that compares the available tools can highlight shared features, gaps, and future research needs, supporting a more unified understanding of social inclusion in mental health. Systematic review registration PROSPERO 2025 CRD420251009903.